/*
  This file is part of drd, a data race detector.

  Copyright (C) 2006-2007 Bart Van Assche
  bart.vanassche@gmail.com

  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation; either version 2 of the
  License, or (at your option) any later version.

  This program is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  02111-1307, USA.

  The GNU General Public License is contained in the file COPYING.
*/


#include "drd_malloc_wrappers.h"
#include "drd_thread.h"
#include "pub_tool_basics.h"
#include "pub_tool_execontext.h"
#include "pub_tool_hashtable.h"
#include "pub_tool_libcassert.h"
#include "pub_tool_libcbase.h"
#include "pub_tool_libcprint.h"
#include "pub_tool_mallocfree.h"
#include "pub_tool_options.h"
#include "pub_tool_replacemalloc.h"
#include "pub_tool_threadstate.h"
#include "pub_tool_tooliface.h"


/*------------------------------------------------------------*/
/*--- Definitions                                          ---*/
/*------------------------------------------------------------*/


typedef struct _DRD_Chunk {
   struct _DRD_Chunk* next;
   Addr          data;            // ptr to actual block
   SizeT         size : (sizeof(UWord)*8)-2; //size requested; 30 or 62 bits
   ExeContext*   where;           // where it was allocated
} DRD_Chunk;

static StartUsingMem s_start_using_mem_callback;
static StopUsingMem  s_stop_using_mem_callback;
/* Stats ... */
static SizeT cmalloc_n_mallocs  = 0;
static SizeT cmalloc_n_frees    = 0;
static SizeT cmalloc_bs_mallocd = 0;


/*------------------------------------------------------------*/
/*--- Tracking malloc'd and free'd blocks                  ---*/
/*------------------------------------------------------------*/

/* Record malloc'd blocks. */
static VgHashTable drd_malloc_list = NULL;


/* Allocate its shadow chunk, put it on the appropriate list. */
static
DRD_Chunk* create_DRD_Chunk(ThreadId tid, Addr p, SizeT size)
{
   DRD_Chunk* mc = VG_(malloc)(sizeof(DRD_Chunk));
   mc->data      = p;
   mc->size      = size;
   mc->where     = VG_(record_ExeContext)(tid, 0);

   return mc;
}

/*------------------------------------------------------------*/
/*--- client_malloc(), etc                                 ---*/
/*------------------------------------------------------------*/

/* Allocate memory and note change in memory available */
static
__inline__
void* drd_new_block(ThreadId tid,
                    SizeT size, SizeT align,
                    Bool is_zeroed)
{
   Addr p;

   cmalloc_n_mallocs ++;

   // Allocate and zero
   p = (Addr)VG_(cli_malloc)(align, size);
   if (!p) {
      return NULL;
   }
   if (is_zeroed) VG_(memset)((void*)p, 0, size);
   s_start_using_mem_callback(p, p + size);

   // Only update this stat if allocation succeeded.
   cmalloc_bs_mallocd += size;

   VG_(HT_add_node)(drd_malloc_list, create_DRD_Chunk(tid, p, size));

   return (void*)p;
}

static
void* drd_malloc(ThreadId tid, SizeT n)
{
   return drd_new_block(tid, n, VG_(clo_alignment), /*is_zeroed*/False);
}

static
void* drd_memalign(ThreadId tid, SizeT align, SizeT n)
{
   return drd_new_block(tid, n, align, /*is_zeroed*/False);
}

static
void* drd_calloc(ThreadId tid, SizeT nmemb, SizeT size1)
{
   return drd_new_block(tid, nmemb*size1, VG_(clo_alignment),
                        /*is_zeroed*/True);
}

static
__inline__
void drd_handle_free(ThreadId tid, Addr p)
{
   DRD_Chunk* mc;

   cmalloc_n_frees++;

   mc = VG_(HT_remove)(drd_malloc_list, (UWord)p);
   if (mc == NULL)
   {
      tl_assert(0);
   }
   else
   {
      tl_assert(p == mc->data);
      s_stop_using_mem_callback(mc->data, mc->data + mc->size);
      VG_(cli_free)((void*)p);
      VG_(free)(mc);
   }
}

static
void drd_free(ThreadId tid, void* p)
{
   drd_handle_free(tid, (Addr)p);
}

static
void* drd_realloc(ThreadId tid, void* p_old, SizeT new_size)
{
   DRD_Chunk* mc;
   void*     p_new;
   SizeT     old_size;

   cmalloc_n_frees ++;
   cmalloc_n_mallocs ++;
   cmalloc_bs_mallocd += new_size;

   /* Remove the old block */
   mc = VG_(HT_remove)(drd_malloc_list, (UWord)p_old);
   if (mc == NULL) {
      tl_assert(0);
      return NULL;
   }

   old_size = mc->size;

   if (old_size == new_size)
   {
      /* size unchanged */
      mc->where = VG_(record_ExeContext)(tid, 0);
      p_new = p_old;
      
   }
   else if (old_size > new_size)
   {
      /* new size is smaller */
      s_stop_using_mem_callback(mc->data + new_size, mc->data + old_size);
      mc->size = new_size;
      mc->where = VG_(record_ExeContext)(tid, 0);
      p_new = p_old;

   }
   else
   {
      /* new size is bigger */
      /* Get new memory */
      const Addr a_new = (Addr)VG_(cli_malloc)(VG_(clo_alignment), new_size);

      if (a_new)
      {
         /* Copy from old to new */
         VG_(memcpy)((void*)a_new, p_old, mc->size);

         /* Free old memory */
         s_stop_using_mem_callback(mc->data, mc->data + mc->size);
         VG_(free)(mc);

         // Allocate a new chunk.
         mc = create_DRD_Chunk(tid, a_new, new_size);
         s_start_using_mem_callback(a_new, a_new + new_size);
      }
      else
      {
         /* Allocation failed -- leave original block untouched. */
      }

      p_new = (void*)a_new;
   }  

   // Now insert the new mc (with a possibly new 'data' field) into
   // malloc_list.  If this realloc() did not increase the memory size, we
   // will have removed and then re-added mc unnecessarily.  But that's ok
   // because shrinking a block with realloc() is (presumably) much rarer
   // than growing it, and this way simplifies the growing case.
   VG_(HT_add_node)(drd_malloc_list, mc);

   return p_new;
}

static
void* drd___builtin_new(ThreadId tid, SizeT n)
{
   void* const result = drd_new_block(tid, n, VG_(clo_alignment), /*is_zeroed*/False);
   //VG_(message)(Vg_DebugMsg, "__builtin_new(%d, %d) = %p", tid, n, result);
   return result;
}

static
void drd___builtin_delete(ThreadId tid, void* p)
{
   //VG_(message)(Vg_DebugMsg, "__builtin_delete(%d, %p)", tid, p);
   drd_handle_free(tid, (Addr)p);
}

static
void* drd___builtin_vec_new(ThreadId tid, SizeT n)
{
   return drd_new_block(tid, n, VG_(clo_alignment), /*is_zeroed*/False);
}

static
void drd___builtin_vec_delete(ThreadId tid, void* p)
{
   drd_handle_free(tid, (Addr)p);
}

void drd_register_malloc_wrappers(const StartUsingMem start_using_mem_callback,
                                  const StopUsingMem stop_using_mem_callback)
{
   tl_assert(drd_malloc_list == 0);
   drd_malloc_list = VG_(HT_construct)("drd_malloc_list");   // a big prime
   tl_assert(drd_malloc_list != 0);
   tl_assert(stop_using_mem_callback);

   s_start_using_mem_callback = start_using_mem_callback;
   s_stop_using_mem_callback  = stop_using_mem_callback;

   VG_(needs_malloc_replacement)(drd_malloc,
                                 drd___builtin_new,
                                 drd___builtin_vec_new,
                                 drd_memalign,
                                 drd_calloc,
                                 drd_free,
                                 drd___builtin_delete,
                                 drd___builtin_vec_delete,
                                 drd_realloc,
                                 0);
}

Bool drd_heap_addrinfo(Addr const a,
                       Addr* const data,
                       SizeT* const size,
                       ExeContext** const where)
{
   DRD_Chunk* mc;

   tl_assert(data);
   tl_assert(size);
   tl_assert(where);

   VG_(HT_ResetIter)(drd_malloc_list);
   while ((mc = VG_(HT_Next)(drd_malloc_list)))
   {
      if (mc->data <= a && a < mc->data + mc->size)
      {
         *data  = mc->data;
         *size  = mc->size;
         *where = mc->where;
         return True;
      }
   }
   return False;
}

/*------------------------------------------------------------*/
/*--- Statistics printing                                  ---*/
/*------------------------------------------------------------*/

void drd_print_malloc_stats(void)
{
   DRD_Chunk* mc;
   SizeT     nblocks = 0;
   SizeT     nbytes  = 0;
   
   if (VG_(clo_verbosity) == 0)
      return;
   if (VG_(clo_xml))
      return;

   /* Count memory still in use. */
   VG_(HT_ResetIter)(drd_malloc_list);
   while ((mc = VG_(HT_Next)(drd_malloc_list)))
   {
      nblocks++;
      nbytes += mc->size;
   }

   VG_(message)(Vg_DebugMsg, 
                "malloc/free: in use at exit: %lu bytes in %lu blocks.",
                nbytes, nblocks);
   VG_(message)(Vg_DebugMsg, 
                "malloc/free: %lu allocs, %lu frees, %lu bytes allocated.",
                cmalloc_n_mallocs,
                cmalloc_n_frees, cmalloc_bs_mallocd);
   if (VG_(clo_verbosity) > 1)
      VG_(message)(Vg_DebugMsg, " ");
}

/*--------------------------------------------------------------------*/
/*--- end                                                          ---*/
/*--------------------------------------------------------------------*/

/*
 * Local variables:
 * c-basic-offset: 3
 * End:
 */
